Chamfer attachment for hand planes



y 1952 P. J. MASTRIPOLITO 2,597,158

CHAMFER ATTACHMENT FOR HAND PLANES Filed Oct. 13, 1950 r \S: IW I null INVENTOR. PHIL/P J? MASTR/POL/TO ATTORNEYS.

Patented May 20, g 1952 UNITED STATE CHAMFER ATTACHMENT FOR HAND PLANES Philip J. Mastripolito, Philadelphia, Pa. Application October 13, 1950, Serial No. 189;909

' 1 Claim. (o1.-1'45-2o) The object of the invention is to provide an attachment for a hand plane to facilitate cutting, with accuracy, along the corner adjacent the end and one side of a board stock, a bevel of predetermined precise width and degree, and which may also be adapted to other uses, such as a guide for use in making a straight and measured molding on the edge, or side nearest the edge, of the stock.

Preferred embodiments of the invention are illustrated in the accompanying drawings.

Fig. 1 is a perspective view of a hand plane with the attachment applied thereto.

Fig. 2 is a front view of the attachment and of the part of the plane to which it is attached.

Fig. 3 is a side view of Fig. 2.

Fig. 4 is a partial front view of a modification.

Fig. 5 is a detail view of the calibrated shaft.

Fig. 6 is a partial front view of a modification adapted to allow the production of a wider bevel.

To the plane P, shown in Fig. 1, which illustrates a conventional hand plane, is secured one embodiment of the attachment, the details of which are shown in Fig. 2.

Secured to opposite side flanges I of the plane are brackets ll each carrying a holding block (5. Each bracket Il may be of an inverted U- form and the terminal arm of the U may be securely abutted against the inside of the side flange ill by means of a bolt l2. Both brackets may be so secured, or one or both brackets may be of the simplified form shown in Fig. 4, the bracket [3 being merely an arm upstanding from the holder [6 and abutted against the side flange ill of the plane by means of a bolt [4 and washer l5.

Each holding block l6 has an orifice of polygonal form (preferably rectangular), through which extends a shaft IQ of corresponding contour carrying a parallel bar 20 extending lengthwise of the plane. This bar may be of various shapes. For convenience of illustration, each of the two bars is shown of the shape of a right angle triangle. The two sides adjoining the right angle are of equal width, one side being carried by the parallel shaft l9 and the other side extending under the plane. The side corresponding to the hypothenuse extends (with the other two sides of equal width), at an angle of 45 degrees to the bottom of the plane.

It is clear that if a board B is positioned in the space between these two parallel bars, and is'rigidly held during the back and forth movement of the plane, the plane may be operated to form a bevel edge across the corner of the board,

" which bevel will be precisely at an angle of 45 to-the'end and one side of the board.

The width of the bevel depends upon the distance between the two parallel bars 20. To predetermine this distance with accuracy, the shaft 19 is formed with calibrations l8 stamped on its side. The markings may be separated by suitable fractions of an inch, say long markings spaced apart one half of an inch and intermediate short markings spaced apart one sixteenth of an inch. If, for example, the operator desires to form a bevel of a width of one half inch, either parallel, or both parallels, may be slid in its block until certain calibrations on the outer ends registering with the outer face of the holding block indicate that the approximating corners of the parallels 20 are spaced apart one half inch.

It will be understood that the thumb screw I1 is loosened to allow adjustment of the shaft l9 and is tightened after adjustment to hold the shaft [9 firmly in adjusted position.

It will be understood that if it is desired to form a bevel on the stock of an angle other than 45, the shaft [9 and the bars 20 carried thereby will be replaced by shafts carrying parallel bars whose longer sides extend, when applied to the plane, at appropriate angles. Thus if it is desired to form a 30 bevel, two parallel bars will be provided whose longer sides will extend crosswise, when applied to the plane, at respectively 30 and angles. A very few such pairs of parallel bars will sufiice for use in forming bevels of the few different degrees of inclination that are ordinarily required.

The construction shown in Fig. 2 will permit the two parallel bars to be spaced apart the distance required to form as wide a bevel as may be ordinarily desired. If, however, it is desired to provide for still wider bevels, the bracket ll may be connected with the holding block l6 by a laterally extending arm 2|, as shown in Fig. 6, of such length as to permit adjustment for a bevel having a width nearly or quite the width of the cutting knife of the plane.

The forward ends of the parallel bars should extend beyond the front end of the plane (say, for example, one inch), while the rearward ends should extend beyond the edge of the cutter K (say, for example, from one-fourth to one-half inch).

It is preferred to so construct the device that when positioned on the plane the top of each parallel bar will rest flush against the bottom of the plane, thus adding firmness and strength to the attachment.

It will be understood that the use of the device is not limited to the formation of corner bevels as hereinbefore described. The inner face of the bevel may, for example, extend, when applied to the plane, perpendicularly thereto, as, for instance, when the operator desires to form straight and measured. moulding on the edge of the stock or on the side nearest such edge.

What is claimed is:

A device for attachment to hand planes comprising two main unitary pieces, one a holding parallel bar having an inner face corresponding to the predetermined degree of the bevel to be 15 formed on the stock and in rigidrelation with ing on its outer end portions calibrations adapted, by said sliding movement, to be adjusted to register with the holding block, and a thumb screw by means of which the shaft and the parallel bar carried thereby are secured in such adjusted position and in rigid relation with the block, its supporting bracket and the plane.

PHILIP J; MASTR-IPOLITO.

REFERENCES CITED The following: references are of record in the tile of this patent:

UNJLTED STATES PATENTS Number: Name Date 273,073 Haynes Feb. 27, 1883 853,453,. Smith Dec. 4, 1883 661,559 Smith Nov. 13, 1900 83015451. 'Braut-'.;. Sept. 11., 1906 Potter" Oct. 17, 1922 

